U.S. patent application number 10/181381 was filed with the patent office on 2003-04-03 for hydrophilizing agent, hydrophilizing fluid , and method of hydrophilizing.
Invention is credited to Kawaguchi, Motoya, Nakada, Kazuya.
Application Number | 20030065085 10/181381 |
Document ID | / |
Family ID | 18536324 |
Filed Date | 2003-04-03 |
United States Patent
Application |
20030065085 |
Kind Code |
A1 |
Nakada, Kazuya ; et
al. |
April 3, 2003 |
Hydrophilizing agent, hydrophilizing fluid , and method of
hydrophilizing
Abstract
A hydrophilizing agent comprising: (a) a hydrophilic polymer
which is a copolymer of N-vinylacetamide with a polymerizable
monomer having a COOX group (wherein X means hydrogen, an alkali
metal atom, or an ammonium salt); (b) a water-soluble urethane
resin; and (c) inorganic silica. It imparts hydrophilicity and
corrosion resistance to the surface of a metallic material.
Inventors: |
Nakada, Kazuya; (Tokyo,
JP) ; Kawaguchi, Motoya; (Tokyo, JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
18536324 |
Appl. No.: |
10/181381 |
Filed: |
October 4, 2002 |
PCT Filed: |
January 15, 2001 |
PCT NO: |
PCT/JP01/00197 |
Current U.S.
Class: |
524/538 ;
427/385.5 |
Current CPC
Class: |
C08G 18/6266 20130101;
F28F 13/18 20130101; F28F 2245/02 20130101; F28D 17/005 20130101;
C08G 18/0823 20130101; C09D 139/00 20130101; C09D 175/04 20130101;
C08L 75/04 20130101; C09D 139/02 20130101; C09D 139/00 20130101;
C08L 2666/14 20130101; C08L 2666/54 20130101; C09D 139/02 20130101;
C08L 2666/14 20130101; C08L 2666/54 20130101; C09D 175/04 20130101;
C08L 2666/10 20130101 |
Class at
Publication: |
524/538 ;
427/385.5 |
International
Class: |
C08J 003/00; C08L
077/00; C08L 051/00; B05D 003/02; C08K 003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 17, 2000 |
JP |
2000-7978 |
Claims
1. A hydrophilization agent characterized in that it contains (a) a
hydrophilic polymer, i.e., a copolymer of N-vinylacetamide and a
polymerizable monomer having a COOX group (in the formula, X means
hydrogen atom, alkali metal atom or ammonium salt), (b)
water-soluble urethane resin, and (c) inorganic silica.
2. A hydrophilization agent according to claim 1, wherein in the
hydrophilic polymer (a), the ratio of the N-vinylacetamide and the
polymerizable monomer having a COOX group (in the formula, X means
hydrogen atom, alkali metal atom or ammonium salt) is within a
weight ratio of 95:5.about.20:80.
3. A hydrophilization agent according to claim 1, wherein said
water-soluble urethane resin (b) is a heat-reactive aliphatic
urethane resin including a blocked isocyanate group in the
molecule.
4. A hydrophilization agent according to claim 1, wherein (c) said
inorganic silica is water-dispersing coagulating colloidal silica
having from 1.about.200 nm of particle diameter.
5. A hydrophilization agent according to any one of claims 1
through 4, wherein it further contains at least one additive
selected from a group consisting of an anti-bacteria/mildew agent,
a surfactant and a cross-linking agent.
6. A hydrophilization agent according to any one of claims 1
through 4, wherein 10.about.1000 parts by weight of (b) the
water-soluble urethane resin and (c) 10.about.1000 parts by weight
of (c) the inorganic silica are blended relative to 100 parts by
weight of (a) said hydrophilic polymer.
7. A hydrophilization agent according to claim 6, wherein it
further contains at least one additive selected from a group
consisting of anti-bacteria/mildew agent, a surfactant and a
cross-linking agent.
8. A hydrophilization liquid characterized in that it contains
1.about.100 g/l, of a hydrophilization agent, which contains (a) a
hydrophilic polymer, i.e., a copolymer of N-vinylacetamide and a
polymerizable monomer having a COOX group (in the formula, X means
hydrogen atom, alkali metal atom or ammonium salt), (b)
water-soluble urethane resin, and (c) inorganic silica.
9. A hydrophilization liquid according to claim 8, wherein in the
hydrophilic polymer (a), the ratio of the N-vinylacetamide and the
polymerizable monomer having a COOX group (in the formula, X means
hydrogen atom, alkali metal atom or ammonium salt) is within a
weight ratio of 95:5.about.20:80.
10. A hydrophilization agent according to claim 8, wherein said
water-soluble urethane resin (b) is a heat-reactive aliphatic
urethane resin including a blocked isocyanate group in the
molecule.
11. A hydrophilization liquid according to claim 8, wherein (c)
said inorganic silica is water-dispersing coagulating colloidal
silica having from 1.about.200 nm of particle diameter.
12. A hydrophilization liquid according to any one of claims 8
through 11 wherein the hydrophilization agent contains at least one
additive selected from a group consisting of an
anti-bacteria/mildew agent, a surfactant and a cross linking
agent.
13. A hydrophilization liquid according to any one of claims 8
through 11, wherein 10.about.1000 parts by weight of (b) the
water-soluble urethane and 10.about.1000 parts by weight of (c) the
organic silica are blended relative to 100 parts by weight of (a)
said hydrophilic polymer.
14. A hydrophilization liquid according to claim 13, wherein the
hydrophilization agent further contains at least one additive
selected from a group consisting of an anti-bacteria/mildew agent,
a surfactant and a cross linking agent.
15. A hydrophilization method characterized in that, a
hydrophilization agent, which contains (a) a hydrophilic polymer,
i.e., a copolymer of N-vinylacetamide and a polymerizable monomer
having a COOX group (in the formula, X means hydrogen atom, alkali
metal atom or ammonium salt), (b) water-soluble urethane resin, and
(c) inorganic silica, is deposited on the surface of metallic
material and dried to form a hydrophilic film.
16. A hydrophilization method according to claim 15, wherein in the
hydrophilic polymer (a), the ratio of N-vinylacetamide and a
polymerizable monomer having a COOX group (in the formula, X means
hydrogen atom, alkali metal atom or ammonium salt) is preferably
within a weight ratio of 95:5.about.20:80.
17. A hydrophilization method according to claim 15, wherein said
water-soluble urethane resin (b) is a heat-reactive aliphatic
urethane resin including a blocked isocyanate group in the
molecule.
18. A hydrophilization method according to claim 15, wherein (e)
said inorganic silica is water-dispersing coagulating colloidal
silica having from 1.about.200 nm of particle diameter.
19. A hydrophilization method according to any one of claims
15.about.18, wherein the hydrophilization agent further contains at
least one additive selected from a group consisting of an
anti-bacteria and an anti-mildew agent, a surfactant and a
cross-linking agent.
20. A hydrophilization method according to any one of claims 15
through 18, wherein 10.about.1000 parts by weight of (b) the
water-soluble urethane resin and 10.about.1000 parts by weight of
(c) the inorganic silica are blended relative to 100 parts by
weight of (a) said hydrophilic polymer.
21. A hydrophilization method according to claim 20, wherein the
hydrophilization agent further contains at least one additive
selected from a group consisting of an anti-bacteria/mildew agent,
a surfactant and a cross-linking agent.
22. A hydrophilization method characterized in that, a
hydrophilization liquid, which contains 1.about.100 g/L of a
hydrophilization agent containing (a) a hydrophilic polymer, i.e.,
a copolymer of N-vinylacetamide and a polymerizable monomer having
a COOX group (in the formula, X means hydrogen atom, alkali metal
atom or ammonium salt), (b) water-soluble urethane resin, and (c)
inorganic silica, is deposited on the surface of metallic material
and dried to form a hydrophilic film.
23. A hydrophilization method according to claim 22, wherein in the
hydrophilic polymer (a), the ratio of the N-vinylacetamide and the
polymerizable monomer having a COOX group (in the formula, X means
hydrogen atom, alkali metal atom or ammonium salt) is within a
weight ratio of 95:5.about.20:80.
24. A hydrophilization method according to claim 8, wherein said
water-soluble urethane resin (b) is a heat-reactive aliphatic
urethane resin including a blocked isocyanate group in the
molecule.
25. A hydrophilization method according to claim 22, wherein (c)
said inorganic silica is water-dispersing coagulating colloidal
silica having from 1.about.200 nm of particle diameter.
26. A hydrophilization method according to any one of claims 22
through 25, wherein the hydrophilization agent further contains at
least one additive selected from a group consisting of an
anti-bacteria/mildew agent, a surfactant and a cross linking
agent.
27. A hydrophilization method according to any one of claims 22
through 25, wherein 10.about.1000 parts by weight of (b) the
water-soluble urethane and 10.about.1000 parts by weight of (c) the
inorganic silica are blended relative to 100 parts by weight of (a)
said hydrophilic polymer.
28. A hydrophilization method according to claim 27, wherein the
hydrophilization agent further contains at least one additive
selected from a group consisting of anti-bacteria/mildew agent, a
surfactant and a cross linking agent.
Description
TECHNICAL FIELD
[0001] The present invention relates to a novel hydrophilization
agent, hydrophilization liquid, and hydrophilization method, which
can impart improved hydrophilicity and corrosion resistance on the
surface of metallic material, such as aluminum, aluminum-alloy,
copper, copper-alloy, stainless steel and the like, particularly in
a case where these materials are used for a heat exchanger.
BACKGROUND TECHNIQUE
[0002] Generally, most heat exchangers made of metallic material,
such as an aluminum-containing metallic material, are so designed
that their heat-dissipating and cooling portions have surface area
as large as possible to enhance the heat-dissipating and cooling
performance. In addition, the inter-fin space is extremely narrow
to minimize the size of the heat exchanger. Therefore, when an
evaporator is operated, moisture in the atmosphere condenses on the
fin surface. The condensed water tends to form water drops which
fill the fin gaps (clogging), when the hydrophilicity of the fin
surface is poor. As a result, ventilation resistance is increased,
which leads to reduction of the heat-exchanging efficiency. Such
problems then arise as power loss, generation of noise, and the
water drops scattering with the air stream to downstream side.
[0003] Several methods are therefore proposed and implemented for
hydrophilization-treating the fin surfaces of a heat exchanger, so
as to prevent water drops from filling the fin gaps and hence to
improve the water wettability.
[0004] The methods for imparting hydrophilicity to the surface of
metallic material are roughly classified into two types. One is an
organic-inorganic composite type, in which an organic
macromolecules are incorporated or added into an inorganic
compound, particularly silica fine particles. The other method is
an organic type mainly composed of an organic macromolecules free
of silica.
[0005] For example, Japanese Examined Patent Publication (kokoku)
No. 7-109355 discloses a heat exchanger, in which the former,
composite organic-inorganic type is applied, and which comprises
tubes and fins formed of aluminum. In this heat exchanger, a film
is formed on a part or the entire surface of the aluminum and
consists, at least in its surface, of a compound having a silanol
group (--SiOH) and polyvinyl pyrrolidone. This film has excellent
initial hydrophilicity. However, since its resistance to water
solubility is poor, it is difficult to maintain the hydrophilicity
for a long period of time. In addition, there remain problems
unsolved with regard to foreign odor and lubricating property
during the fin formation.
[0006] In addition, a hydrophilization agent for the heat exchanger
disclosed in Japanese Unexamined Patent Publication (kokai)
No.8-60031 contains water-dispersing silica (A), aqueous
polyurethane resin (B), and an aqueous blocked polyurethane
prepolymer (C). A hydrophilization method using this agent is
disclosed. However, it cannot be said that the hydrophilicity
persistence of the film is satisfactory.
[0007] Next, for example, Japanese Unexamined Patent Publication
(kokai) No. 4-366182 is related to the latter organic type. It is
disclosed that the hydrophilization surface-treating agent
comprises, in terms of the solid matter, (a) 0.5.about.6 parts by
weight of polyvinyl pyrrolidone having 50.about.1000 of
polymerization degree, and (b) 1.about.10 parts by weight of
polyvinyl alcohol having 80% or more of saponification degree and
100.about.1000 of polymerization degree, and further the agent has
(a)/[(a)+(b)] in a range of 0.1.about.0.9. A hydrophilization
surface-treating bath and a hydrophilization surface-treating
method, for which the hydrophilization surface-treating agent
mentioned above is used, are disclosed. However, the corrosion
resistance and the resistance of the film to solubility in water,
formed by this treating agent are unsatisfactory.
[0008] In addition, Japanese Unexamined Patent Publication No.
6-322552 discloses an organic type with improved hydrophilicity and
corrosion resistance, suppression of and foreign odor, that is, a
hydrophilization surface treating agent, which contains 5.about.50
parts by weight of polyacrylic acid and 5.about.50 parts by weight
of polyethylene oxide, based on 100 parts by weight of the
composition, which consists, in terms of solid matter, 5.about.25
parts by weight of sodium salt and/or potassium salt of
carboxymethylcellulose, 25.about.50 parts by weight of ammonium
salt of carboxymethylcellulose, and 25.about.70 parts by weight of
N-methylolacrylamide. It is disclosed to use the hydrophilic
surface-treating agent mentioned above for a hydrophilization
surface-treating bath and a hydrophilization surface-treating
method of aluminum material. The film formed by this method has
poor hydrophilicity persistence.
[0009] As is described above, such hydrophilization agent which
enables improved hydrophilicity persistence and corrosion
resistance to be imparted to a heat exchanger has not been
established at present.
[0010] The present invention solves the above-mentioned problems
involved in the prior art. Specifically the present invention
provides a hydrophilization agent, hydrophilization liquid, and
hydrophilization method, which can impart improved hydrophilicity
and corrosion resistance on the surface of metallic materials, the
raw material of which is aluminum, aluminum alloy, copper, copper
alloy, stainless steel and the like.
DISCLOSURE OF INVENTION
[0011] The present inventors exhaustively considered measures for
solving the problems involved in the prior art mentioned above. As
a result, it was newly found that a film having improved
hydrophilicity and corrosion resistance can be formed on the
surface of metallic material by using a hydrophilization agent and
hydrophilization liquid, which contains a hydrophilic polymer, that
is, a copolymer of N-vinylacetamide and a polymerizable monomer
having a COOX group (in the formula, X means hydrogen atom, alkali
metal atom or ammonium salt), water-soluble urethane resin, and
inorganic silica. As a result, the present invention has been
completed.
[0012] Namely, the hydrophilization agent according to the present
invention is characterized in that it contains, as the essential
components, (a) a hydrophilic polymer, that is, a copolymer of
N-vinylacetamide and a polymerizable monomer having a COOX group
(in the formula, X means hydrogen atom, alkali metal atom or
ammonium salt), (b) water-soluble urethane resin, and (c) inorganic
silica. In the hydrophilic polymer (a) mentioned above, the ratio
of N-vinylacetamide and a polymerizable monomer having a COOX group
(in the formula, X means hydrogen atom, alkali metal atom or
ammonium salt) are preferably within the weight ratio of
95:5.about.20:80. The above-mentioned water-soluble urethane resin
(b) is preferably heat-reactive, aliphatic urethane resin having a
blocked isocyanate group in the molecule. In addition, the
above-mentioned inorganic silica (c) is preferably water-dispersing
coagulating colloidal silica having 1.about.200 nm of the particle
diameter. Preferably, at least one additive selected from the group
consisting of anti-bacteria anti-mildew agent, a surfactant, and
cross-linking agent is contained. In addition, it is preferable
that 10.about.1000 parts by weight of water-soluble urethane resin
(b) and 10.about.1000 parts by weight of the inorganic silica (c)
are blended at a weight ratio relative to 100 parts by weight of
the above-mentioned hydrophilic polymer (a). Next, the
hydrophilization liquid of the present invention is characterized
in that it contains the above-mentioned hydrophilization agent at a
concentration of 1.about.100 g/L. In addition, the hydrophilization
method of the present invention is characterized in that the
hydrophilization agent or hydrophilization liquid mentioned above
is deposited on the surface of metallic material and is dried to
form the hydrophilization film.
[0013] The constitutions of the present invention are described
hereinafter in detail.
[0014] The hydrophilic polymer (a), which is an essential component
of the hydrophilization agent or hydrophilization liquid according
to the present invention, is effective to impart the persistence of
hydrophilicity and to suppress the generation of foreign odor. A
polymerizable monomer, which is copolymerized with the
N-vinylacetamide in the hydrophilic polymer (a) is not particularly
limited, provided that it is a polymerizable organic acid having a
COOX group (in the formula, X means hydrogen atom, alkali metal
atom or ammonium salt). As example, itaconic acid, maleic acid,
maleic acid anhydride, crotonic acid, acrylic acid, (metha) acrylic
acid, or their salts are listed. Among them, acrylic acid, (metha)
acrylic acid and their salts are preferred. Particularly, acrylic
acid and/or its alkali metal or ammonium salts are preferred from
the viewpoint of the resistance to solubility in water. As such
compounds, acrylic acid, sodium acrylate, potassium acrylate,
ammonium acrylate are listed. One or more of these compounds can be
used.
[0015] In the hydrophilic polymer (a), that is, a copolymer of
N-vinylacetamide and a polymerizable monomer having a COOX group
(in the formula, X means hydrogen atom, alkali metal atom or
ammonium salt), the weight ratio of N-vinylacetamide and the
polymerizable monomer is preferably 95:5.about.20:80, more
preferably 90:10.about.30:70, further preferably 70:30.about.50:50.
When the polymerizable monomer is less than 95:5 of weight ratio,
resistance of the film formed to solubility in water is poor. On
the other hand, when the polymerizable monomer is more than 20:80,
the persistence of hydrophilicity is lowered.
[0016] The water-soluble urethane resin (b), which is an essential
component of the hydrophilization agent and hydrophilization liquid
according to the present invention, is used to fix the inorganic
silica (c) in the hydrophilic film formed. That is, the
water-soluble urethane resin (b) plays the role of binder in the
hydrophilic film, and suppresses the scattering of the silica fine
particles. As a result, improved hydrophilicity and corrosion
resistance and suppression of aggressive odor and the like can be
ensured for a long period of time. A hydrophilic film, which is
soft, elastic and highly shrinkable, can be obtained due to the
characteristic of the urethane resin. This seems to be the reason
that the wear resistance, the flexing property, resistance to
solubility in water, chemical resistance, low-temperature and beat
resistance and durability of the film are improved. Accordingly, it
is believed that, even when an anti-bacteria agent and/or an
anti-mildew agent are added to the hydrophilization agent or
hydrophilization liquid of the present invention, the film
dissolves out only slightly. Premature solution of the
anti-bacteria agent and/or the anti mildew agent is suppressed,
with the result that the anti-bacteria and anti-mildew effects can
be sustained in excellent manner.
[0017] As to the water-soluble urethane resin (b), its kind is not
particularly limited, provided that polyisocyanate and polyol are
used as the main raw materials, and the isocyanate group and
hydroxyl group are brought into reaction to form a water-soluble
compound having an urethane bond in the molecule. Its molecular
weight is generally in a range of from ten thousand to five
million, preferably from one hundred thousand to three million,
more preferably from two hundred thousand to two million. In
addition, the liquid state, such as colloid dispersion, emulsion
and the like, as well as the ionic property, such as nonionic,
anionic property, cationic property and the like are not
particularly limited. As representative examples of polyisocyanate
are hexamethylene diisocyanate, tetramethylene diisocyanate,
tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate,
1,5-naphthalene diisocyante and the like are listed. As
representative examples of polyol are aliphatic polyesterpolyol,
aromatic polyesterpolyol, polyetherpolyol, polycarbonatediol,
polysiloxanepolyol, polybudadiene polyol, polyolefin polyol,
acrylpolyol and the like are listed.
[0018] In addition, the water-soluble urethane resin (b) is
preferably a heat-reactive aliphatic urethane resin having a
blocked isocyanate group among various urethanes from the viewpoint
of the persistence of hydrophilicity. As various blocking agent for
blocking the isocyanate group, lower alcohol, phenol, aliphatic
mercaptan, prussic acid, secondary aromatic amine, oxime, active
methylene compound, lactum, and bisulfite and the like are
listed.
[0019] The inorganic silica (c), which is an essential component of
the hydrophilization agent and hydrophilization liquid of the
present invention, has very high affinity to water, because the
silanol group (Si-OH) present in the molecule reacts with water via
the hydrogen bond. Improved hydrophilicity can be ensured by means
of mixing this inorganic silica (c) in the hydrophilic film.
[0020] The inorganic silica (c) is not particularly limited to as
its kind, provided that a silanol group is present in the molecule.
As such inorganic silica, water-dispersing coagulating colloidal
silica, pulverous fumed silica capable of dispersing in water, and
alkali silicate, SiO.sub.2/M.sub.2O (in the equation, M designates
the alkali metal, such as lithium, sodium, potassium and the like)
usually referred to as the water glass are listed. The
water-dispersing coagulating colloidal silica is preferably used
among them, from the viewpoint of liquid-stability and
hydrophilicity. In addition, its particle diameter is preferably in
a range of from 1 to 200 nm, more preferably in a range of from 5
to 100 nm. When its diameter is less than 1 nm, the hydrophilicity
of the hydrophilic film formed is poor. On the other hand, when its
particle diameter is more than 200 nm, the strength of film is low
so that adhesion with the metallic material is lowered.
[0021] An anti-bacteria agent and/or anti-mildew agent may be added
into the hydrophilization agent and hydrophilization liquid of the
present invention so as to suppress the putrefaction odor due to
propagation of bacteria, mildew and yeast, provided that the
effects of the present invention are not impeded. Desirably, the
anti-bacteria/mildew agent usable in the present invention is such
that can resist, during the drying step after depositing the
hydrophilization agent or hydrophilization liquid, the heating for
removal of water, which is a solvent of the treatment agent or
treatment liquid. That is, the decomposition temperature of the
anti-bacteria/mildew agent is preferably approximately 100.degree.
C. or more.
[0022] Such anti-bacteria and/or anti-mildew agent is selected, for
example, from 5-chloro-2-methyl-4-isothiazoline-3-on,
2-methyl-4-isothiazoline-3-on, 2-(4-thiocyano-methylthio)
benzothizole, 2,2-dibromo-3-nitrilopropyon amide, sodiumethylene
bis (dithiocarbamate), sodium-2-pyridionethiol-1-oxide,
zinc-2-pyridinethiol-1-oxide, 2,2'-dithiobis-(pyridine-1-oxide),
2,4,5,6-tetrachloro isophthalonitorile, 2-methylcarbonyl
aminobenzilimidazaole,
2,3,5,6-tetrachloro-4-(methylsulfonyl)-pyridine,
2-(4-thyazolyl)-benzimid- azole, N-(fluorodichloromethyl thio)
sulfamide, p-chloro-m-xylenol, dehydroacetic acid, 0-phenylphenol,
1,2-benzisothiazoline-3-on, 1,2-benzisothyazoline barium,
diiodemethyl-p-toluenesulfone, 2-n-octyl-4-isothyazaoline-3-on,
10,10'-oxybisphenoxyarsine, 1,2-dibromo-2,4-dicyanobutane,
2-bromo-2-nitropropane-diol, p-oxypropyl benzonatepropyl,
3-iode-2-propylbutylcarbamate, 1,3-dimethylol-5,5'-dimet-
hylhydratoin, 1 or 3-monodimethylol-5,5'-dimethylhidantoin, and
various inorganic anti-bacteria agents, such as Ag-based
agents.
[0023] The addition amount of the anti-bacteria and/or anti-mildew
agent is preferably 0.1.about.30 parts by weight, more preferably
from 1.about.20 parts by weight, relative to 100 parts by weight of
the total weight of the components (a), (b) and (c). When the
addition amount is less than 0.1 parts by weight, the film formed
does not satisfactorily exhibit anti-bacteria and anti-mildew
resistance. On the other hand, when the addition amount exceeds 30
parts by weight, its effects saturate and the cost of the treating
agent and the treating liquid uneconomically increases and hence
the agent becomes impracticable.
[0024] If necessary to further improve the lubricating property of
the film formed by using the hydrophilization agent or the
hydrophilization liquid of the present invention, or to improve the
depositing wettablity of the agent or the liquid on the surface of
the metallic material, a surfactant may be added, if necessary. The
surfactant used for this purpose is not limited and may be any one
of the anionic, cationic, nonionic or amphoteric surfactants.
However, it is preferable not to use a surfactant having an ionic
property opposite to that of the components (a), (b) and (c) used
in a combination with the surfactant, since the stability of the
treating liquid may be adversely affected.
[0025] The following are examples of surfactants capable of adding
into the hydrophilization agent or hydrophilization liquid of the
present invention: non-ionic surfactant, such as polyoxyethylene
alkylether, e.g. polyoxyethylene laurylether and polyoxyethylene
stearylether, polyoxyethylene alkylphenylether, e.g.,
polyoxethylene nonyl-phenlylether, sorbitan fatty acid ester, e.g.,
a block polymer of oxyethylene and oxypropylene (Pluronic),
sorbitan monolaurate and sorbitan monostearate, fatty acid ester of
polyoxyethylen, e.g., polyoxyethylene laurate, polyoxyethylene
stearate, and polyoxy-ethylene oleate, glycerin fatty acid ester,
and polyoxyethylene propylene glycol alkyl phenol ether; anionic
surfactant such as fatty acid salt, e.g., sodium laurate, sodium
stearate and sodium olealate, alkyl sulfate, e.g., sodium
dodecylsulfate, alkylsulfosuccinate, dialkylsulfosuccinate,
alkenylsulfosuccinate and polyoxyethylene alkyl sulfate; cationic
surfactant, such as alkylamine salt, e.g., stearylaminde acetate,
quaternary ammonium salt, e.g., stearylamine acetate, quaternary
ammonium salt, e.g., strearyltrimethyl ammonium alkylbetaine, e.g.,
lauryl betaine, and amineoxide; and, amphoteric surfactant such as
aminoproyonate and; alkyl dimethyl betaine. In addition,
fluorine-based amphoteric surfactant and silicon-based surfactant
are used.
[0026] The addition amount of the above-mentioned surfactant is
preferably in a range of 0.05.about.20 parts by weight, more
preferably 0.1.about.10 parts by weight relative to 100 parts by
weight of the total weight of the components (a), (b) and (c). When
the addition amount is less than 0.05 parts by weight, the
hydrophilization film does not exhibit satisfactory lubrication
property. On the other hand, when the addition amount exceeds 20
parts by weight, there arises disadvantageously a danger that the
adhesiveness of the film on the metallic material is lowered.
[0027] In the present invention, a cross-linking agent can be used
to further enhance the resistance of the hydrophilic film to
solubility in water. The cross-linking agent, which is contained in
the hydrophilization agent and hydrophilization liquid of the
present invention, is preferably a water-soluble organic
cross-linking agent, for example, polymethylol, polyglycidine,
polyaziridile compound and aldehydes. Namely, it can be selected
from polymethylol melamine, methylol urea, methylolized
polyacrylamide, polyethylene glycol, diglycidylether,
diaziridilated polyethylene oxide, glyoxal, furfural and the
like.
[0028] The addition amount of the cross-linking agent mentioned
above is preferably in a range of from 0.1.about.50 parts by weight
relative to 100 parts by weight of the total weight of the
components (a), (b) and (c) used in combination. When this addition
amount is less than 0.1 parts by weight, the cross-linking effect
is poor. On the other hand, when the addition amount exceeds 50
parts by weight, the hydrophilization film becomes so hard as to
embrittle. Furthermore, there is a danger that the formability and
adhesiveness with the metallic material are disadvantageously
lowered.
[0029] In the hydrophilization agent of the present invention, it
is preferable to blend the water-soluble urethane resin (b) and
inorganic silica (c) mentioned above with the hydrophilic polymer
(a) mentioned above at a weight ratio 10.about.1000 parts by weight
of (b) and 10.about.1000 parts by weight of (c) relative to 100
parts by weight of (a). More preferably, 20.about.500 parts by
weight of water-soluble urethane resin (b) and 50.about.700 parts
by weight of inorganic silica (c) relative to 100 parts by weight
of the hydrophilic polymer (a). When the blending weight ratio of
the water-soluble urethane resin (b) is less than 10 parts by
weight, the resistance of the formed film to solubility in water is
unsatisfactory. On the other hand, when the blending weight ratio
exceeds 1000 parts by weight, the hydrophilicity of the film is
disadvantageously lowered. In addition, when the blending weight
ratio of the inorganic silica (c) is less than 10 parts by weight,
the hydrophilicity of the film formed is unsatisfactory. On the
other hand, when the blending weight ratio exceeds 1000 parts by
weight, there is a danger that a problem of aggressive odor arises
and flexibility of the film is lowered.
[0030] In the hydrophilization treating liquid of the present
invention, the hydrophilization agent mentioned above is contained
preferably at a concentration of 1.about.100 g/L, more preferably
at a concentration range of 5.about.50 g/L. When the concentration
is less than 1 g/L, it is difficult to ensure such film thickness
as to demonstrate such functions as the hydrophilicity and
corrosion resistance. On the other hand, when the concentration
exceeds 100 g/L, its effects saturate and the agent becomes
economically impracticable.
[0031] The solvent of the hydrophilization agent and
hydrophilization liquid of the present invention is mainly composed
of water. There is no problem at all to additionally use a
water-soluble solvent such as various alcohols, ethers, ketones and
glycols so as to adjust and improve the drying speed. In addition,
one or more of rust-proof agent, leveling agent, filler, colorant,
antifoamer may be into the hydrophilization agent or
hydrophilization liquid of the present invention, in a range where
neither the gist of the present invention nor the film properties
are impaired.
[0032] The hydrophilization agent and the hydrophilization liquid
of the present invention is used as is, or as the surface-treatment
liquid, in which the agent is diluted with water. The concentration
and the viscosity of the treatment liquid are adjusted
appropriately to meet the application method on the surface of the
metallic material, the targeted thickness of the film and the
like.
[0033] A method for depositing the hydrophilization agent or
hydrophilization liquid on the surface of metallic material is not
particularly limited, and may be any one of the application methods
with a roll coater, brush and the like, dipping method, flow-coat
method, injection method, and spraying method. The contact time at
the deposition on the surface of metallic material is not
particularly limited.
[0034] The drying method after depositing the hydrophilization
agent and hydrophilization liquid of the present invention is not
particularly limited. Usually, it is preferable to use a hot-blast
oven and the like and to dry in a temperature range of
50.about.300.degree. C., more preferably 100.about.250.degree. C.
When the drying temperature is less than 50.degree. C., the film
formation does not advance satisfactorily, so that corrosion
resistance and resistance of the film to solubility in water are
poor. On the other hand, when the drying temperature exceeds
300.degree. C., there is a danger that a problem of foreign odor
arises.
[0035] Preferably, the post-drying thickness of the hydrophilic
film formed by using the hydrophilization agent and
hydrophilization liquid of the present invention is within a range
of 0.05.about.5 .mu.m, more preferably from 0.1.about.2 .mu.m. When
the film thickness is less than 0.05 .mu.m, it is difficult to
impart satisfactory hydrophilicity. On the other hand, when the
film thickness exceeds 5 .mu.m, there is a possibility that the
heat conductivity is disadvantageously lowered.
[0036] In a preferable hydrophilization method of the present
invention, the surface of the metallic material is degreased and
washed, or pre-treated by chemical conversion and the like for the
purpose of enhancing the corrosion resistance and the like.
Subsequently, the hydrophilization agent and the hydrophilization
liquid are deposited on the surface of the metallic material and
are heated and dried so as to form a hydrophilic film. As the
chemical conversion treatment for enhancing the corrosion
resistance, anodic oxidation treatment, boemite treatment, chromic
chromate treatment, and various non-chromate treatments
(zirconium-based, titanium-based, vanadium-based, cerium-based,
zinc phosphate-based, silane-coupling based, resin-based and the
like) are listed,
BEST MODE FOR CARRYING OUT INVENTION
[0037] Examples as well as Comparative Examples are shown
hereinbelow. The effects of the hydrophilization agent and liquid
and the hydrophilization method of the present invention are more
specifically described. However, the scope of the present invention
is not limited by these examples.
[0038] Test Samples
[0039] An aluminum-alloy sheet (JIS-3004, dimension 70 mm.times.150
mm, sheet thickness--0.12 mm) was used.
[0040] Treatment Condition
[0041] A hydrophilization-treated sheet was manufactured by means
of the treatments in the sequence of the following process
[1].fwdarw.[2].fwdarw.[3].fwdarw.[4].fwdarw.[5].fwdarw.[6].fwdarw.[7].fwd-
arw.[8]
[0042] [1] Degreasing (65.degree. C., 2 minutes, dipping
method)
[0043] Aqueous solution of a commercially available, alkaline
detergent agent (registered trademark, Fine Cleaner 315, product of
Nihon Parkerizing Co., Ltd. 3% solution)
[0044] [2] Water Washing (normal temperature, 30 seconds, spraying
method)
[0045] [3] Chemical Conversion Treatment (40.degree. C., 1 minute,
dipping method)
[0046] Aqueous solution of a commercially available, chromate
phosphate chemical conversion treatment agent (mixed solution of 4%
of registered trademark, Alchrome K702SL and 0.3% of registered
trademark Alchrome K702AC, both products of Nihon Parkerizing Co.,
Ltd.) was used to form a chromate phosphate film (Cr depositing
amount--50.about.60 mg/m.sup.2) on the aluminum-alloy sheet.
[0047] [4] Water Washing (normal temperature, 30 seconds, spraying
method)
[0048] [5] Washing with Deionized Water (normal temperature, 30
seconds, spraying method)
[0049] [6] Hydro-extracting Drying (50.degree. C., 3 minutes,
drying in a hot-blast oven)
[0050] [7] Hydrophilization Treatment
[0051] The total content of the non-volatile matter of the
hydrophilization liquid was adjusted to 3%. The so-adjusted
hydrophilization liquid was applied on the sheet, which was treated
by the chromate phosphate mentioned above, by means of a bar coater
No. 10 (thickness of the hydrophilization film after heating and
drying is 0.4 to 0.5 .mu.m). The hydrophilization agent was
prepared by using the components and additives mentioned above. The
composition of the hydrophilization liquid is shown in Table 1.
Examples 1-10 are shown in Table 2. Comparative Examples 1-7 are
shown in Table 3.
[0052] [8] Heating and Drying (150.degree. C., 10 minutes, a
hot-blast drier)
[0053] (a) Hydrophilic Polymer
[0054] {circle over (1)} Copolymer of NVA/sodium acrylate=30/70
(weight ratio)
[0055] {circle over (2)} Copolymer of NVA/acrylic acid=60/40
(weight ratio)
[0056] {circle over (3)} Copolymer of NVA/potassium acrylate=90/10
(weight ratio)
[0057] {circle over (4)} Polymer of NVA alone
[0058] {circle over (5)} Polyacrylic acid
[0059] Remarks: NVA--N-vinylacetamide
[0060] (b) Water-soluble urethane resin
[0061] {circle over (1)} polyether-based aliphatic urethane resin
(nonionic, containing a blocked isocyanate group)
[0062] {circle over (2)} polyether-based aromatic urethane resin
(anionic, containing a blocked isocyanate group)
[0063] {circle over (3)} polyester-based aliphatic urethane resin
(anionic, containing a blocked isocyanate group)
[0064] {circle over (4)} polyester-based aliphatic urethane resin
(anionic, without a blocked isocyanate group)
[0065] (c) Inorganic Silica
[0066] {circle over (1)} Water dispersing coagulating colloidal
silica (particle diameter: 40.about.100 nm)
[0067] {circle over (2)} Pulverous fumed silica (gas-phase silica,
particle diameter: 0.3 .mu.m)
[0068] {circle over (3)} Potassium silicate (water glass,
SiO.sub.2/K.sub.2O=3/1 (mole ratio))
[0069] (d) Additive
[0070] (Anti Bacteria Agent)
[0071] {circle over (1)} Zinc-2-pyridinethiol-1-oxide
[0072] (Surfactant)
[0073] {circle over (2)} Anionic surfactant (Product of Sanyo Kasei
Kogyo Co., Ltd. Eleminol JS-2: alkylallylsulfo sodiumsuccinate)
[0074] (Cross-Linking Agent)
[0075] {circle over (3)} Glyoxal
[0076] In Comparative Example 1, the hydrophilic polymer is not a
copolymer. The hydrophilic film is formed by a polymer of
N-vinylacetamide alone.
[0077] In Comparative Example 2, the hydrophilic film is formed by
a hydrophilic polymer, which does not contain at all a copolymer
polymerized by using N-vinylacetamide.
[0078] In Comparative Example 3, the hydrophilic film formed does
not contain water-soltuble urethane.
[0079] In Comparative Example 4, the hydrophilic film formed does
not contain inorganic silica.
[0080] Comparative Example 5 is Example 9 of Japanese Examined
Patent Publication (kokoku) No. 7-109355.
[0081] Comparative Example 6 is Example 3 of Japanese Unexamined
Patent Publication (kokai) No. 8-60031
[0082] Comparative Example 7 is Example 1 of Japanese Unexamined
Patent Publication No. 4-366182
[0083] Evaluation Method
[0084] (1) Hydrophilicity Persistence
[0085] The hydrophilization treated sheets mentioned above were
immersed in de-ionized water at room temperature for 72 hours.
Drying was carried out at 80.degree. C. for 5 minutes. The contact
angle of water on the hydrophilization-treated sheet was measured
by FACE contact angle tester (type: CA-P, Product of Kyowa Kaimen
Kagaku Co., Ltd.)
[0086] The evaluation criterion of the hydrophilicity persistence
is as follows.
[0087] (Water Contact Angle)
[0088] .circleincircle.: less than 10.degree.
[0089] .largecircle.: 10.degree. or more, less than 20.degree.
[0090] .DELTA.: 20.degree. or more, less than 30.degree.
[0091] .times.: 30.degree. or more
[0092] (2) Resistance to Solubility in Water
[0093] The hydrophilization treated sheets mentioned above were
immersed in de-ionized water at room temperature for 72 hours.
Drying was carried out at 80.degree. C. for 5 minutes. The weight
difference of the hydrophilic film prior and subsequent to
immersion was obtained. The dissolving ratio in water was then
obtained by the following formula.
Solution Ratio in Water (%)={(initial weight of film-weight of film
after immersion/initial weight of film).times.100
[0094] The evaluation criterion of resistance of solubility to
water is as follows.
[0095] (Ratio of Solution in Water)
[0096] .circleincircle.: less than 10%
[0097] .largecircle.: 10% or more, less than 30%
[0098] .DELTA.: 30% or more, less than 50%
[0099] .times.: 50% or more
[0100] (3) Corrosion Resistance
[0101] The salt-spray test based on JIS-Z-2371 was carried out.
After spraying for 240 hours, the state of corrosion generation on
the samples was evaluated by the naked eye. The evaluation
criterion of the corrosion resistance is as follows.
[0102] (Area Ratio of Corrosion)
[0103] .circleincircle.: less than 10%
[0104] .largecircle.: 10% or more, less than 30%
[0105] .DELTA.: 30% or more, less than 50%
[0106] .times.: 50% or more
[0107] (4) Prevention of Aggressive Odor
[0108] The hydrophilization treated sheets mentioned above were
immersed in de-ionized water at room temperature for 72 hours,
followed by drying at 80.degree. C. for 1 hour and then exposure to
the water vapor of boiled de-ionized water for approximately 1
second. The aggressive odor was quickly smelled and evaluated.
Evaluation criterion of the prevention of foreign odor is as
follows.
[0109] (Sensual Foreign Odor)
[0110] .circleincircle.: no appreciable foreign odor at all
[0111] .largecircle.: somewhat appreciable foreign odor
[0112] .DELTA.: evidently appreciable foreign odor
[0113] .times.: very strong appreciable foreign odor
[0114] The evaluation results are shown in Table 1 and Table 2.
[0115] As is apparent from the evaluation results of Table 1 and
Table 2, the hydrophilic film of Examples 1 through 10, which was
formed by using the hydrophilization agent, the hydrophilization
liquid and the hydrophilization method of the present invention,
exhibits improved hydrophilicity persistence, resistance to
solubility in water, corrosion resistance, and prevention of
aggressive odor generation. Contrary to this, in the hydrophilic
film of Comparative Examples 1 through 7, several properties are
unsatisfactory and do not attain the level to fulfill the
practically requested functions.
[0116] Industrial Applicability
[0117] As is apparent from the descriptions hereinabove, it became
possible that a hydrophilic film having hydrophilicity persistence,
resistance to solubility in water, corrosion resistance, and
prevention of aggressive odor generation is formed by means of
applying the hydrophilization agent, the hydrophilization liquid
and the hydrophilization method according to the present invention
to the metallic material.
[0118] Consequently, the hydrophilization agent, the
hydrophilization liquid and the hydrophilization method according
to the present invention are extremely useful in practice.
1TABLE 1 Composition, Condition and Evaluation Results in Examples
1.about.10 Composition of Hydrophilic Treating Liquid (Components
and Blending Weight Parts) Evaluation Result (a) (b) (c) Resistance
Prevention of Hydrophilic Urethane Inorganic (d) Hydrophilicity to
Solubility Corrosion Foreign Odor polymer resin Silica Additive
Persistence in water Resistance Generation Example 1 {circle over
(1)} 100 {circle over (2)} 20 {circle over (1)} 100 {circle over
(1)} 10 .circleincircle. .largecircle. .circleincircle.
.circleincircle. {circle over (2)} 3 {circle over (3)} 15 Example 2
{circle over (2)} 100 {circle over (3)} 600 {circle over (1)} 900
-- -- .circleincircle. .circleincircle. .circleincircle.
.largecircle. Example 3 {circle over (3)} 100 {circle over (3)} 400
{circle over (1)} 500 {circle over (1)} 50 .circleincircle.
.largecircle. .circleincircle. .largecircle. {circle over (2)} 5
Example 4 {circle over (1)} 50 {circle over (4)} 50 {circle over
(1)} .RTM. {circle over (2)} 3 .largecircle. .largecircle.
.largecircle. .circleincircle. {circle over (3)} 50 {circle over
(3)} 10 Example 5 {circle over (2)} 100 {circle over (1)} 200
{circle over (1)} 400 {circle over (2)} 5 .circleincircle.
.circleincircle. .circleincircle. .largecircle. Example 6 {circle
over (2)} 100 {circle over (3)} 200 {circle over (3)} 200 {circle
over (2)} 2 .circleincircle. .largecircle. .circleincircle.
.largecircle. Example 7 {circle over (2)} 100 {circle over (3)} 150
{circle over (1)} 50 {circle over (2)} 3 .largecircle.
.largecircle. .circleincircle. .circleincircle. {circle over (3)}
30 Example 8 {circle over (2)} 100 {circle over (1)} 50 {circle
over (2)} 20 {circle over (2)} 3 .largecircle. .largecircle.
.largecircle. .circleincircle. {circle over (3)} 50 Example 9
{circle over (2)} 80 {circle over (3)} 300 {circle over (1)} 250
{circle over (1)} 50 .circleincircle. .circleincircle.
.circleincircle. .largecircle. {circle over (3)} 20 {circle over
(3)} 250 {circle over (3)} 50 Example 10 {circle over (1)} 100
{circle over (1)} 150 {circle over (1)} 450 {circle over (2)} 5
.circleincircle. .largecircle. .circleincircle. .largecircle.
{circle over (3)} 150 {circle over (2)} 10
[0119]
2TABLE 2 Composition, Condition and Evaluation Results in
Comparative Examples 1.about.7 Composition of Hydrophilic Treating
Liquid (Components and Blending Weight Parts) Evaluation Result (a)
(b) (c) Resistance Prevention of Hydrophilic Urethane Inorganic (d)
Hydrophilicity to Solubility Corrosion Foreign Odor polymer resin
Silica Additive Persistence in water Resistance Generation
Comparative {circle over (4)} 100 {circle over (3)} 150 {circle
over (1)} 50 {circle over (2)} 3 .DELTA. .DELTA. .circleincircle.
.circleincircle. Example 1 {circle over (3)} 30 Comparative {circle
over (5)} 100 {circle over (3)} 200 {circle over (3)} 200 {circle
over (2)} 2 .DELTA. .largecircle. .DELTA. .DELTA. Example 2
Comparative {circle over (2)} 100 -- -- {circle over (1)} 300
{circle over (2)} 2 .largecircle. .DELTA. .largecircle. X Example 3
Comparative {circle over (2)} 100 {circle over (3)} 200 -- --
{circle over (2)} 2 X .DELTA. .largecircle. .circleincircle.
Example 4 Comparative Example 9 of Japanese Examined Patent
.largecircle. .DELTA. .largecircle. .DELTA. Example 5 Publication
No.7-109355 Comparative Example 3 of Japanese Unexamined Patent
.DELTA. .circleincircle. .circleincircle. .largecircle. Example 6
Publication No. 8-60031 Comparative Example 1 of Japanese
Unexamined Patent X .DELTA. .largecircle. .largecircle. Example 7
Publication 4-366182
* * * * *